[mythtv-users] sql query to identify duplicates

[R. G. Newbury]

On 30/04/14 11:46 AM, Leo Butler wrote:
>>    From: "Michael T. Dean" <mtdean at thirdcontact.com>
>>    On 04/30/2014 09:47 AM, Leo Butler wrote:
>>    > Hi,
>>    >
>>    > Since changing over from an analogue (pvr-150) to digital (hdhr3-cc)
>>    > tuner, I have written a custom recording rule to re-record episodes.
>>    > I simply modified the custom rule to re-record sdtv recordings when
>>    > available as hdtv.
>>    >
>>    > I would like to write an sql query to identify duplicate recordings,
>>    > in order to delete the older recording. I am no sql guru, and my first
>>    > thought was to query the recorded.duplicate field--but this is set to
>>    > 1 for all recordings, so the name belies its purpose.
>>    >
>>    > Any suggestions?
>>
>>    http://www.mythtv.org/wiki/FindDuplicateRecordings , but ideally you'd
>>    modify it so it operates on all recordings and so that things like
>>    category can be specified in the command line or interactively--and
>>    especially so that deletes are confirmed interactively.  Lots of
>>    examples at http://www.mythtv.org/wiki/Category:Python_Scripts (those by
>>    Raymond Wagner being excellent examples of how to do things properly
>>    with the Python bindings he wrote :).
>>
>>    This would be a much better "whole" solution than using SQL (which can't
>>    do the rest--like delete and such).
>
> Mike, thanks for the comments, but I am looking for an sql query.
> I guess I'll need to rtfm.
>

Try something like this:

SELECT field, COUNT(field) FROM table GROUP BY field HAVING 
(COUNT(field) > 1);

for example ( querying the mysql database as root)

select user, count(user) from user group by user having (count(user) > 1);
+--------+-------------+
| user   | count(user) |
+--------+-------------+
| mythtv |           4 |
+--------+-------------+

( Yes, the mysql database has a field called user, in a table called 
user!. And I have 4 entries for the mythtv user  at localhost, 127.0.0.1 
etc)

Geoff


-- 
              R. Geoffrey Newbury